Runaway subduction (Talk.Origins)
- Baumgardner's computer model shows that runaway subduction explains how the global flood occurred. The cold, heavy crust of the ocean floor sinks into the lighter, hotter mantle, releasing gravitational potential energy as heat. Runaway subduction posits that this process greatly accelerated: "As the plates deform the surrounding rock, the mechanical energy of deformation is converted into heat, creating a superheated 'envelope' of silicate around the sinking ocean floor. Silicate is very sensitive to heat, so it becomes weaker, allowing the plates to sink faster and heating the envelope still further, and so on, faster and faster. As the plates pull apart, the gap between them grows into a broadening seam in the planet. This sends a gigantic bubble of mantle shooting up through these ridges; [w]hich displaces the oceans; [w]hich creates a huge flood" (Burr 1997, 57). God "caused an enormous blob of hot mantle material to come rushing up at incredible velocity through the underwater midocean ridges. The material ballooned, displacing a tidal wave of sea water over the continents. . . . Then, after 150 days (Genesis 7:24), the bubble retreated with equal speed into the Earth" (Burr 1997, 56).
Source: Burr, Chandler, 1997. The geophysics of God. US News and World Report 122 (June 16): 55-58.
While Catastrophic Plate Tectonics is an interesting model, its heat problem is hard to swallow. Other possibilities should be considered and eliminated before it should seriously be considered. If these difficulties could be solved, then maybe it would be more viable, but in its present state it is not credible, or is incomplete. (Talk.Origins quotes in blue)
1. Baumgardner's theory still does not work without miracles, as Baumgardner himself admitted (Baumgardner 1990a, 1990b). The thermal diffusivity of the earth would have to increase ten thousandfold to get the subduction rates proposed, and something would have to cause the advance and retreat of the magma bubble (Matsumura 1997). Miracles would also have been necessary to cool the new ocean floor and to raise sedimentary mountains in months rather than in the millions of years it would ordinarily take.
2. The miraculously lowered viscosity would likely also lower frictional heating, removing the heat source that the model needs to accelerate the subduction (Matsumura 1997).
According to Genesis 6:11-17 the Flood was an act of divine judgement and as such it would be by definition a miraculous event. So this is only a problem in the Evolutionary world of absolute naturalism.
Responses 3-4 are problematic, particularly the huge amount of heat involved in this theory. While there is no doubt that God could have handled it, there is still no doubt that heat is a big problem for this model. The following reference is the best source of material available on this topic.
Reference: Plate Tectonics Questions and Answers
6. Cenozoic sediments are post-Flood according to this model. Yet fossils from Cenozoic sediments alone show a sixty-five-million-year record of evolution, including a great deal of the diversification of mammals and angiosperms.
This statement assumes both uniformitarian geology and macro evolution, and as such it is a case of your theory does not work under my theory, so your theory must be wrong.
7. Terra, the computer program that Baumgardner created, is a useful computer program for modeling convection, but the program adds no credibility. Unreal assumptions of runaway subduction will produce unreal conclusions.
The same could be said when the uniformitarian plate subduction model is plugged in to this program.